Search results for: estimated discharge date

Authors: Pello Alfonso-Muniozguren, Madeleine Bussemaker, Ralph Chadeesingh, Caryn Jones, David Oakley, Judy Lee, Devendra Saroj

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Current industrialized livestock agriculture is growing every year leading to an increase in the generation of wastewater that varies considerably in terms of organic content and microbial population. Therefore, suitable wastewater treatment methods are required to ensure the wastewater quality meet regulations before discharge. In the present study, a combined lab scale activated sludge-filtration-ozonation system was used to treat a pre-treated abattoir wastewater. A hydraulic retention time of 24 hours and a solid retention time of 13 days were used for the activated sludge process, followed by a filtration step (4-7 µm) and using ozone as tertiary treatment. An average reduction of 93% and 98% was achieved for Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD), respectively, obtaining final values of 128 mg/L COD and 12 mg/L BOD. For the Total Suspended Solids (TSS), the average reduction increased to 99% in the same system, reducing the final value down to 3 mg/L. Additionally, 98% reduction in Phosphorus (P) and a complete inactivation of Total Coliforms (TC) was obtained after 17 min ozonation time. For Total Viable Counts (TVC), a drastic reduction was observed with 30 min ozonation time (6 log inactivation) at an ozone dose of 71 mg O3/L. Overall, the combined process was sufficient to meet discharge requirements without further treatment for the measured parameters (COD, BOD, TSS, P, TC, and TVC).

Keywords: abattoir waste water, activated sludge, ozone, waste water treatment

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Authors: Nsikan Affiah, Kayode Osungbade, Williams Uzoma

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Malaria remains one of the major killers of humans worldwide, threatening the lives of more than one-third of the world’s population. Some people refers it to; a disease of poverty because it contributes towards national poverty through its impact on foreign direct investment, tourism, labour productivity, and trade. At the micro level, it may cause poverty through spending on health care, income losses, and premature deaths. Unfortunately, malaria is a disease that affects both low-income household and its high-income counterpart, but low-income households are still at greater risk because significant part of the available monthly income is dedicated to various preventive and treatment measures. The objective of this study is to estimate direct and indirect cost of malaria treatment in households in a section of South-South Region (Akwa Ibom State) of Nigeria. A cross-sectional study of Six Hundred and Forty (640) heads of households or any adult representative of households in three local government areas of Akwa Ibom State, Nigeria from May 1-31, 2015 were ascertained through interviewer-administered questionnaire adapted from Nigerian Malaria Indicator Survey Report. The clustering technique was used to select 640 households with the help of Primary Health Care (PHC) house numbering system. Using exchange rate of 197 Naira/USD, result shows that direct cost of malaria treatment was 8,894.44 USD while the indirect cost of malaria treatment was 11,012.81 USD. Total cost of treatment made up of 44.7% direct cost and 55.3% indirect cost, with average direct cost of malaria treatment per household estimated at 20.6 USD and the average indirect cost of treatment per household estimated at 25.1 USD. Average total cost for each episode (888) of malaria was estimated at 22.4 USD. While at household level, the average total cost was estimated at 45.5 USD. From the average total cost, low-income households would spend 36% of monthly household income on treating malaria and the impact could be said to be catastrophic, compared to high-income households where only 1.2% of monthly household income is spent on malaria treatment. It could be concluded that the cost of malaria treatment is well beyond the means of households and given the reality of repeated bouts of malaria and its contribution to the impoverishment of households, there is a need for urgent action.

Keywords: direct cost, indirect cost, low income households, malaria

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Authors: Mujahid Manzoor, Muhammad Shafique, Jam Nazeer Ahmad, Farman Ahmad, Muhammad Ali, Muhammad Rizwan Tariq, Shahbaz Ahmad, Muhammad Saleem Haider

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Date palms (P. dactylifera L.) are prominent in the Kingdom of Saudi Arabia (KSA), Iran, UAE, and Iraq, as well as Algeria, Egypt, and Pakistan. Insect pests' attacks on different palm cultivars adversely affected their production in the last few decades. Pakistan ranked sixth for date production around the world. The most commercially grown cultivars are Aseel, Dhaki, Falsi, Karbalai, Mozawati, Jan Swore, Kohra, Hillawi, Kohra, and Begum Jhangi. Red palm weevils are considered as hazardous insect pests responsible for economic loss in palm orchards. This research work depicts the infestation of red palm weevils in eleven different palm cultivars (Hillawi, Mozawati, Kechanr, Aseel, Shamrani, Khudravi, Dhaki, Zeri, Kobra, Zaidi, Denda), which frequently grow in different regions of Pakistan through Y-shaped olfactometer analysis. In addition, the level of both antixenosis and antibiosis was spotted by examining the various parameters such as %age lure of weevils of mature females, general count of laid eggs in addition to their activeness. Furthermore, obtained results depicted that a positive contact was established with minimum antixenotic consequence revealed by a cultivar, “Hillawi” among most hold of RPW adults (22.32%), number of eggs laid (16.66%) and egg hatching (84.66%), while other cultivars, including Mozawati, Aseel, Kechanr, Shamrani, Khudravi, Dhaki, Zeri, and Zaidi, exhibited a greater level of antixenosis. Moreover, “Hillawi” documented the maximum number of eggs, while Kechanr, Mozawati, Aseel Kobra, and Denda showed minimum attraction by red palm weevils. Maximum red palm weevils were attracted in an olfactometer assay of sugarcane varieties.

Keywords: P. dactylifera, R. ferrugineus, olfactometer, antixenosis

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Authors: S. Ben Fredj, H. Ghali, M. Ben Rejeb, S. Layouni, S. Khefacha, L. Dhidah, H. Said

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Background: The Intensive Care Unit (ICU) provides continuous care and uses a high level of treatment technologies. Although developed country hospitals allocate only 5–10% of beds in critical care areas, approximately 20% of nosocomial infections (NI) occur among patients treated in ICUs. Whereas in the developing countries the situation is still less accurate. The aim of our study is to assess mortality rates in ICUs and to determine its predictive factors. Methods: We carried out a nested case-control study in a 630-beds public tertiary care hospital in Eastern Tunisia. We included in the study all patients hospitalized for more than two days in the surgical or medical ICU during the entire period of the surveillance. Cases were patients who died before ICU discharge, whereas controls were patients who survived to discharge. NIs were diagnosed according to the definitions of ‘Comité Technique des Infections Nosocomiales et les Infections Liées aux Soins’ (CTINLIS, France). Data collection was based on the protocol of Rea-RAISIN 2009 of the National Institute for Health Watch (InVS, France). Results: Overall, 301 patients were enrolled from medical and surgical ICUs. The mean age was 44.8 ± 21.3 years. The crude ICU mortality rate was 20.6% (62/301). It was 35.8% for patients who acquired at least one NI during their stay in ICU and 16.2% for those without any NI, yielding an overall crude excess mortality rate of 19.6% (OR= 2.9, 95% CI, 1.6 to 5.3). The population-attributable fraction due to ICU-NI in patients who died before ICU discharge was 23.46% (95% CI, 13.43%–29.04%). Overall, 62 case-patients were compared to 239 control patients for the final analysis. Case patients and control patients differed by age (p=0,003), simplified acute physiology score II (p < 10-3), NI (p < 10-3), nosocomial pneumonia (p=0.008), infection upon admission (p=0.002), immunosuppression (p=0.006), days of intubation (p < 10-3), tracheostomy (p=0.004), days with urinary catheterization (p < 10-3), days with CVC ( p=0.03), and length of stay in ICU (p=0.003). Multivariate analysis demonstrated 3 factors: age older than 65 years (OR, 5.78 [95% CI, 2.03-16.05] p=0.001), duration of intubation 1-10 days (OR, 6.82 [95% CI, [1.90-24.45] p=0.003), duration of intubation > 10 days (OR, 11.11 [95% CI, [2.85-43.28] p=0.001), duration of CVC 1-7 days (OR, 6.85[95% CI, [1.71-27.45] p=0.007) and duration of CVC > 7 days (OR, 5.55[95% CI, [1.70-18.04] p=0.004). Conclusion: While surveillance provides important baseline data, successful trials with more active intervention protocols, adopting multimodal approach for the prevention of nosocomial infection incited us to think about the feasibility of similar trial in our context. Therefore, the implementation of an efficient infection control strategy is a crucial step to improve the quality of care.

Keywords: intensive care unit, mortality, nosocomial infection, risk factors

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Authors: Ahmad Umar, Sheikh Akbar, Ahmed A. Ibrahim, Mohsen A. Alhamami

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The development of advanced materials for energy storage and gas sensing applications has gained significant attention in recent years. In this study, we synthesized and characterized PANI@MnO2@rGO ternary nanocomposites (NCs) to explore their potential in supercapacitors and gas sensing devices. The ternary NCs were synthesized through a multi-step process involving the hydrothermal synthesis of MnO2 nanoparticles, preparation of PANI@rGO composites and the assembly to the ternary PANI@MnO2@rGO ternary NCs. The structural, morphological, and compositional characteristics of the materials were thoroughly analyzed using techniques such as XRD, FESEM, TEM, FTIR, and Raman spectroscopy. In the realm of gas sensing, the ternary NCs exhibited excellent performance as NH3 gas sensors. The optimized operating temperature of 100 °C yielded a peak response of 15.56 towards 50 ppm NH3. The nanocomposites demonstrated fast response and recovery times of 6 s and 10 s, respectively, and displayed remarkable selectivity for NH3 gas over other tested gases. For supercapacitor applications, the electrochemical performance of the ternary NCs was evaluated using cyclic voltammetry and galvanostatic charge-discharge techniques. The composites exhibited pseudocapacitive behavior, with the capacitance reaching up to 185 F/g at 1 A/g and excellent capacitance retention of approximately 88.54% over 4000 charge-discharge cycles. The unique combination of rGO, PANI, and MnO2 nanoparticles in these ternary NCs offer synergistic advantages, showcasing their potential to address challenges in energy storage and gas sensing technologies.

Keywords: paniI@mnO2@rGO ternary NCs, synergistic effects, supercapacitors, gas sensing, energy storage

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Authors: Hadi Farhadian, Homayoon Katibeh

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In this paper, groundwater seepage into Amirkabir tunnel has been estimated using analytical and numerical methods for 14 different sections of the tunnel. Site Groundwater Rating (SGR) method also has been performed for qualitative and quantitative classification of the tunnel sections. The obtained results of above-mentioned methods were compared together. The study shows reasonable accordance with results of the all methods unless for two sections of tunnel. In these two sections there are some significant discrepancies between numerical and analytical results mainly originated from model geometry and high overburden. SGR and the analytical and numerical calculations, confirm the high concentration of seepage inflow in fault zones. Maximum seepage flow into tunnel has been estimated 0.425 lit/sec/m using analytical method and 0.628 lit/sec/m using numerical method occurred in crashed zone. Based on SGR method, six sections of 14 sections in Amirkabir tunnel axis are found to be in "No Risk" class that is supported by the analytical and numerical seepage value of less than 0.04 lit/sec/m.

Keywords: water Seepage, Amirkabir Tunnel, analytical method, DEM, SGR

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Authors: Mohammadamin Hashemi, Mohammadreza Kashizadeh

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Droughts pose a significant threat to sustainable water resource management, agriculture, and socioeconomic sectors, particularly in the field of climate change. This study investigates drought simulation using rainfall-runoff modelling in the Cuneo district, Italy, over the past 60-year period. The study leverages the TUW model, a lumped conceptual rainfall-runoff model with a semi-distributed operation capability. Similar in structure to the widely used Hydrologiska Byråns Vattenbalansavdelning (HBV) model, the TUW model operates on daily timesteps for input and output data specific to each catchment. It incorporates essential routines for snow accumulation and melting, soil moisture storage, and streamflow generation. Multiple catchments' discharge data within the Cuneo district form the basis for thorough model calibration employing the Kling-Gupta Efficiency (KGE) metric. A crucial metric for reliable drought analysis is one that can accurately represent low-flow events during drought periods. This ensures that the model provides a realistic picture of water availability during these critical times. Subsequent validation of monthly discharge simulations thoroughly evaluates overall model performance. Beyond model development, the investigation delves into drought analysis using the robust Standardized Runoff Index (SRI). This index allows for precise characterization of drought occurrences within the study area. A meticulous comparison of observed and simulated discharge data is conducted, with particular focus on low-flow events that characterize droughts. Additionally, the study explores the complex interplay between land characteristics (e.g., soil type, vegetation cover) and climate variables (e.g., precipitation, temperature) that influence the severity and duration of hydrological droughts. The study's findings demonstrate successful calibration of the TUW model across most catchments, achieving commendable model efficiency. Comparative analysis between simulated and observed discharge data reveals significant agreement, especially during critical low-flow periods. This agreement is further supported by the Pareto coefficient, a statistical measure of goodness-of-fit. The drought analysis provides critical insights into the duration, intensity, and severity of drought events within the Cuneo district. This newfound understanding of spatial and temporal drought dynamics offers valuable information for water resource management strategies and drought mitigation efforts. This research deepens our understanding of drought dynamics in the Cuneo region. Future research directions include refining hydrological modelling techniques and exploring future drought projections under various climate change scenarios.

Keywords: hydrologic extremes, hydrological drought, hydrological modelling, machine learning, rainfall-runoff modelling

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Authors: M. Vimal Raj, S. Sakthivel Murugan

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Underwater images degrade their quality due to atmospheric conditions. One of the major problems in an underwater image is motion blur caused by the imaging device or the movement of the object. In order to rectify that in post-imaging, parameters of the blurred image are to be estimated. So, the point spread function is estimated by the properties, using the spectrum of the image. To improve the estimation accuracy of the parameters, Optimized Polynomial Lagrange Interpolation (OPLI) method is implemented after the angle and length measurement of motion-blurred images. Initially, the data were collected from real-time environments in Chennai and processed. The proposed OPLI method shows better accuracy than the existing classical Cepstral, Hough, and Radon transform estimation methods for underwater images.

Keywords: image restoration, motion blur, parameter estimation, radon transform, underwater

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Authors: Gabriel Efomeh Omolaiye, Olatunji Seminu, Jimoh Ajadi, Yusuf Ayoola Jimoh

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The Nigerian part of the Chad Basin till date has been one of the few critically studied basins, with few published scholarly works, compared to other basins such as Niger Delta, Dahomey, etc. This work was undertaken by the integration of 3D seismic interpretations and the well data analysis of eight wells fairly distributed in block A, Baga/Lake sub-basin in Borno basin with the aim of determining the thickness of Chad, Kerri-Kerri, Fika, and Gongila Formations in the sub-basin. Da-1 well (type-well) used in this study was subdivided into stratigraphic units based on the regional stratigraphic subdivision of the Chad basin and was later correlated with other wells using similarity of observed log responses. The combined density and sonic logs were used to generate synthetic seismograms for seismic to well ties. Five horizons were mapped, representing the tops of the formations on the 3D seismic data covering the block; average velocity function with maximum error/residual of 0.48% was adopted in the time to depth conversion of all the generated maps. There is a general thickening of sediments from the west to the east, and the estimated thicknesses of the various formations in the Baga/Lake sub-basin are Chad Formation (400-750 m), Kerri-Kerri Formation (300-1200 m), Fika Formation (300-2200 m) and Gongila Formation (100-1300 m). The thickness of the Bima Formation could not be established because the deepest well (Da-1) terminates within the formation. This is a modification to the previous and widely referenced studies of over forty decades that based the estimation of formation thickness within the study area on the observed outcrops at different locations and the use of few well data.

Keywords: Baga/Lake sub-basin, Chad basin, formation thickness, seismic, velocity

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Authors: M. R. Al-Rashidi, K. M. El-Naggar, M. F. Al-Hajri

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The fuel cost function describes the electric power generation-cost relationship in thermal plants, hence, it sheds light on economical aspects of power industry. Different models have been proposed to describe this relationship with the quadratic function model being the most popular one. Parameters of second order fuel cost function are estimated in this paper using cuckoo search algorithm. It is a new population based meta-heuristic optimization technique that has been used in this study primarily as an accurate estimation tool. Its main features are flexibility, simplicity, and effectiveness when compared to other estimation techniques. The parameter estimation problem is formulated as an optimization one with the goal being minimizing the error associated with the estimated parameters. A case study is considered in this paper to illustrate cuckoo search promising potential as a valuable estimation and optimization technique.

Keywords: cuckoo search, parameters estimation, fuel cost function, economic dispatch

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Authors: Raj Chavan

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The City of Jal serves a population of approximately 3,500 people, including 2,100 permanent inhabitants and 1,400 oil and gas sector workers and RV park occupants. Over the past three years, Jal's population has increased by about 70 percent, mostly due to the oil and gas industry. The City anticipates that the population will exceed 4,200 by 2020, necessitating the construction of a new wastewater treatment plant (WWTP) because the old plant (aerated lagoon system) cannot accommodate such rapid population expansion without major renovations or replacement. Adhering to discharge permit restrictions has been challenging due to aging infrastructure and equipment replacement needs, as well as increasing nutrient loading to the wastewater collecting system from the additional oil and gas residents' recreational vehicles. The WWTP has not been able to maintain permit discharge standards for total nitrogen of less than 20 mg N/L and other characteristics in recent years. Based on discussions with the state's environmental department, it is likely that the future permit renewal would impose stricter conditions. Given its location in the dry, western part of the country, the City must rely on its meager groundwater supplies and scant annual precipitation. The city's groundwater supplies will be depleted sooner than predicted due to rising demand from the growing population for drinking, leisure, and other industrial uses (fracking). The sole type of reuse the city was engaging in (recreational reuse for a golf course) had to be put on hold because of an effluent water compliance issue. As of right now, all treated effluent is evaporated. The city's long-term goal is to become a zero-waste community that sends all of its treated wastewater effluent either to the golf course, Jal Lake, or the oil and gas industry for reuse. Hydraulic fracturing uses a lot of water, but if the oil and gas industry can use recycled water, it can reduce its impact on freshwater supplies. The City's goal of 100% reuse has been delayed by the difficulties of meeting the constraints of the regular discharge permit due to the large rise in influent loads and the aging infrastructure. The City of Jal plans to build a new WWTP that can keep up with the city's rapid population increase due to the oil and gas industry. Several treatment methods were considered in light of the City's needs and its long-term goals, but MBR was ultimately chosen recommended since it meets all of the permit's requirements while also providing 100 percent beneficial reuse. This talk will lay out the plan for the city to reach its goal of 100 percent reuse, as well as the various avenues for funding the small community that have been considered.

Keywords: membrane bioreactor, nitrogent, reuse, small community

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Authors: Muhammad Tahir Riaz, Khalid Mehmood, Ahmad Waseem Akhtar, Tariq Abbas, Sadaqat Ali, Muhammad Altaf

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Livestock sector contributes around 55.9 and 11.8% to agriculture and GDP respectively, according to economic survey of Pakistan 2013-2014. The goats population has been estimated about 66.6 million (M). Parasitic infestation is a major health problem in goats causing loss in body weight, poor body condition, low birth weights, and difficulty in kidding. Keeping in view the utilization of these animals in the country, a pilot epidemiological survey was conducted to find out the major parasitic problems of goats in and around Derawar fort area, Cholistan. Data regarding 662 fecal samples of goats was collected from 25 tobas of Cholistan during June 2012 to June 2013. All the fecal samples were examined through Direct Smear Method and Salt Flotation Technique for the presence of helminth eggs. External parasites were taken from the various components of the carcass of goat and were conserved in 70% alcohol in hygienic, properly enclosed glass jars that were tagged thoroughly. The collected date was analyzed statistically by Chi-square test to find out the prevalence in goats. Out of 662 goats, 261 (39.42%) were found positive for parasites. 233 (35.20%) goats were found positive for gastrointestinal parasites while 28 (4.23%) were positive for external parasites including ticks 20 (3.02%) and mange 8 (1.21%). The higher prevalence of parasites in the study area may be due to pasture grazing, poor management and lack of extension work. In this regards proper management and control measures should be adopted to minimize the Parasitic Problems.

Keywords: Cholistan, goats, parasite, surveillance

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Authors: D. Olszewska, J. Niewiedzial

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In some types of Li-ion batteries carbon in the form of graphite is used. Unfortunately, carbon materials, in particular graphite, have very good electrochemical properties, but increase their volume during charge/discharge cycles, which may even lead to an explosion of the cell. The cell element may be replaced by a composite material consisting of lithium-titanium oxide Li4Ti5O12 (LTO) modified with copper and nickel ions and carbon derived from sucrose. This way you can improve the conductivity of the material. LTO is appropriate only for applications which do not require high energy density because of its high operating voltage (ca. 1.5 V vs. Li/Li+). Specific capacity of Li4Ti5O12 is high enough for utilization in Li-ion batteries (theoretical capacity 175 mAh·g-1) but it is lower than capacity of graphite anodes. Materials based on Li4Ti5O12 do not change their volume during charging/discharging cycles, however, LTO has low conductivity. Another positive aspect of the use of sucrose in the carbon composite material is to eliminate the addition of carbon black from the anode of the battery. Therefore, the proposed materials contribute significantly to environmental protection and safety of selected lithium cells. New anode materials in order to obtain Li3.8Cu0.1Ni0.1Ti5O12 have been prepared by solid state synthesis using three-way: i) stoichiometric composition of Li2CO3, TiO2, CuO, NiO (A- Li3.8Cu0.1Ni0.1Ti5O12); ii) stoichiometric composition of Li2CO3, TiO2, Cu(NO3)2, Ni(NO3)2 (B-Li3.8Cu0.1Ni0.1Ti5O12); and iii) stoichiometric composition of Li2CO3, TiO2, CuO, NiO calcined with 10% of saccharose (Li3.8Cu0.1Ni0.1Ti5O12-C). Structure of materials was studied by X-ray diffraction (XRD). The electrochemical properties were performed using appropriately prepared cell Li|Li+|Li3.8Cu0.1Ni0.1Ti5O12 for cyclic voltammetry and discharge/charge measurements. The cells were periodically charged and discharged in the voltage range from 1.3 to 2.0 V applying constant charge/discharge current in order to determine the specific capacity of each electrode. Measurements at various values of the charge/discharge current (from C/10 to 5C) were carried out. Cyclic voltammetry investigation was carried out by applying to the cells a voltage linearly changing over time at a rate of 0.1 mV·s-1 (in the range from 2.0 to 1.3 V and from 1.3 to 2.0 V). The XRD method analyzes show that composite powders were obtained containing, in addition to the main phase, 4.78% and 4% TiO2 in A-Li3.8Cu0.1Ni0.1O12 and B-Li3.8Cu0.1Ni0.1O12, respectively. However, Li3.8Cu0.1Ni0.1O12-C material is three-phase: 63.84% of the main phase, 17.49 TiO2 and 18.67 Li2TiO3. Voltammograms of electrodes containing materials A-Li3.8Cu0.1Ni0.1O12 and B-Li3.8Cu0.1Ni0.1O12 are correct and repeatable. Peak cathode occurs for both samples at a potential approx. 1.52±0.01 V relative to a lithium electrode, while the anodic peak at potential approx. 1.65±0.05 V relative to a lithium electrode. Voltammogram of Li3.8Cu0.1Ni0.1Ti5O12-C (especially for the first measurement cycle) is not correct. There are large variations in values of specific current, which are not characteristic for materials LTO. From the point of view of safety and environmentally friendly production of Li-ion cells eliminating soot and applying Li3.8Cu0.1Ni0.1Ti5O12-C as an active material of an anode in lithium-ion batteries seems to be a good alternative to currently used materials.

Keywords: anode, Li-ion batteries, Li₄O₅O₁₂, spinel

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Authors: S. Jamshidi, E. Feizi Ashtiani, M. Ardestani, A. Feizi Ashtiani

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Waste load allocation (WLA) strategies usually intend to find economical policies for water resource management. Water quality trading (WQT) is an approach that uses discharge permit market to reduce total environmental protection costs. This primarily requires assigning discharge limits known as total maximum daily loads (TMDLs). These are determined by monitoring organizations with respect to the receiving water quality and remediation capabilities. The purpose of this study is to compare two approaches of TMDL assignment for WQT policy in small catchment area of Haraz River, in north of Iran. At first, TMDLs are assigned uniformly for the whole point sources to keep the concentrations of BOD and dissolved oxygen (DO) at the standard level at checkpoint (terminus point). This was simply simulated and controlled by Qual2kw software. In the second scenario, TMDLs are assigned using multi objective particle swarm optimization (MOPSO) method in which the environmental violation at river basin and total treatment costs are minimized simultaneously. In both scenarios, the equity index and the WLA based on trading discharge permits (TDP) are calculated. The comparative results showed that using economically optimized TMDLs (2nd scenario) has slightly more cost savings rather than uniform TMDL approach (1st scenario). The former annually costs about 1 M$ while the latter is 1.15 M$. WQT can decrease these annual costs to 0.9 and 1.1 M$, respectively. In other word, these approaches may save 35 and 45% economically in comparison with command and control policy. It means that using multi objective decision support systems (DSS) may find more economical WLA, however its outcome is not necessarily significant in comparison with uniform TMDLs. This may be due to the similar impact factors of dischargers in small catchments. Conversely, using uniform TMDLs for WQT brings more equity that makes stakeholders not feel that much envious of difference between TMDL and WQT allocation. In addition, for this case, determination of TMDLs uniformly would be much easier for monitoring. Consequently, uniform TMDL for TDP market is recommended as a sustainable approach. However, economical TMDLs can be used for larger watersheds.

Keywords: waste load allocation (WLA), water quality trading (WQT), total maximum daily loads (TMDLs), Haraz River, multi objective particle swarm optimization (MOPSO), equity

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Authors: Fujio Akagi, Hiroaki Ito, Shin-Ichi Inage

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The aim of this study is to develop a combustion model that can be applied uniformly to laminar and turbulent premixed flames while considering the effect of the Lewis number (Le). The model considers the effect of Le on the transport equations of the reaction progress, which varies with the chemical species and temperature. The distribution of the reaction progress variable is approximated by a hyperbolic tangent function, while the other distribution of the reaction progress variable is estimated using the approximated distribution and transport equation of the reaction progress variable considering the Le. The validity of the model was evaluated under the conditions of propane with Le > 1 and methane with Le = 1 (equivalence ratios of 0.5 and 1). The estimated results were found to be in good agreement with those of previous studies under all conditions. A method of introducing a turbulence model into this model is also described. It was confirmed that conventional turbulence models can be expressed as an approximate theory of this model in a unified manner.

Keywords: combustion model, laminar flame, Lewis number, turbulent flame

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Authors: Teklay Gebrecherkos

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Background: Serological testing for SARS-CoV-2 plays an important role in epidemiological studies, in aiding the diagnosis of COVID-19 and assess vaccine responses. Little is known about the dynamics of SARS-CoV-2 serology in African settings. Here, we aimed to characterize the longitudinal antibody response profile to SARS-CoV-2 in Ethiopia. Methods: In this prospective study, a total of 102 PCR-confirmed COVID-19 patients were enrolled. We obtained 802 plasma samples collected serially. SARS-CoV-2 antibodies were determined using four lateral flow immune assays (LFIAs) and an electrochemiluminescent immunoassay. We determined longitudinal antibody response to SARS-CoV-2 as well as seroconversion dynamics. Results: Serological positivity rate ranged between 12%-91%, depending on timing after symptom onset. There was no difference in the positivity rate between severe and non-severe COVID-19 cases. The specificity ranged between 90%-97%. Agreement between different assays ranged between 84%-92%. The estimated positive predictive value (PPV) for IgM or IgG in a scenario with seroprevalence at 5% varies from 33% to 58%. Nonetheless, when the population seroprevalence increases to 25% and 50%, there is a corresponding increase in the estimated PPVs. The estimated negative-predictive value (NPV) in a low seroprevalence scenario (5%) is high (>99%). However, the estimated NPV in a high seroprevalence scenario (50%) for IgM or IgG is reduced significantly from 80% to 85%. Overall, 28/102 (27.5%) seroconverted by one or more assays tested within a median time of 11 (IQR: 9–15) days post symptom onset. The median seroconversion time among symptomatic cases tended to be shorter when compared to asymptomatic patients [9 (IQR: 6–11) vs. 15 (IQR: 13–21) days; p = 0.002]. Overall, seroconversion reached 100% 5.5 weeks after the onset of symptoms. Notably, of the remaining 74 COVID-19 patients included in the cohort, 64 (62.8%) were positive for antibodies at the time of enrollment, and 10 (9.8%) patients failed to mount a detectable antibody response by any of the assays tested during follow-up. Conclusions: Longitudinal assessment of antibody response in African COVID-19 patients revealed heterogeneous responses. This underscores the need for a comprehensive evaluation of serum assays before implementation. Factors associated with failure to seroconvert need further research.

Keywords: COVID-19, antibody, rapid diagnostic tests, ethiopia

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Authors: Victor Au, Khin Maung Than, Zaw Win Aung, Linawati Jumat

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Background & Objectives: Cardiac arrests can occur anywhere or anytime, and most of the cases will be brought to the emergency department except the cases that happened in at in-patient setting. Raja IsteriPangiran Anak Saleha (RIPAS) Hospital is the only tertiary government hospital which located in Brunei Muara district and received all referral from other Brunei districts. Data of cardiac arrests in Brunei Darussalam scattered between Emergency Medical Ambulance Services (EMAS), Emergency Department (ED), general inpatient wards, and Intensive Care Unit (ICU). In this audit, we only focused on cardiac arrest cases which had happened or presented to the emergency department RIPAS Hospital. Theobjectives of this audit were to look at demographic of cardiac arrest cases and the survival to discharge rate of In-Hospital Cardiac Arrest (IHCA) and Out-Hospital Cardiac Arrest (OHCA). Methodology: This audit retrospective study was conducted on all cardiac arrest cases that underwent Cardiopulmonary Resuscitation (CPR) in ED RIPAS Hospital, Brunei Muara, in the year 2019-2020. All cardiac arrest cases that happened or were brought in to emergency department were included. All the relevant data were retrieved from ED visit registry book and electronic medical record “Bru-HIMS” with keyword diagnosis of “cardiac arrest”. Data were analyzed and tabulated using Excel software. Result: 313 cardiac arrests were recorded in the emergency department in year 2019-2020. 92% cases were categorized as OHCA, and the remaining 8% as IHCA. Majority of the cases were male with age between 50-60 years old. In OHCA subgroup, only 12.4% received bystander CPR, and 0.4% received Automatic External Defibrillator (AED) before emergency medical personnel arrived. Initial shockable rhythm in IHCA group accounted for 12% compare to 4.9% in OHCA group. Outcome of ED resuscitation, 32% of IHCA group achieved return of spontaneous circulation (ROSC) with a survival to discharge rate was 16%. For OHCA group, 12.35% achieved ROSC, but unfortunately, none of them survive till discharge. Conclusion: Standardized registry for cardiac arrest in the emergency department is required to provide valid baseline data to measure the quality and outcome of cardiac arrest. Zero survival rate for out hospital cardiac arrest is very concerning, and it might represent the significant breach in cardiac arrest chains of survival. Systematic prospective data collection is needed to identify contributing factors and to improve resuscitation outcome.

Keywords: cardiac arrest, OHCA, IHCA, resuscitation, emergency department

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Authors: Sebai Amal, Massuel Sylvain

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Groundwater is the key element of the development of most of the semi-arid areas where water resources are increasingly scarce due to an irregularity of precipitation, on the one hand, and an increasing demand on the other hand. This is the case of the watershed of the Central Tunisia Merguellil, object of the present study, which focuses on an implementation of an underground flows hydrodynamic model to understand the recharge processes of the Kairouan’s plain groundwater by aquifers boundary through the hydraulic threshold of El Haouareb. The construction of a conceptual geological 3D model by the Hydro GeoBuilder software has led to a definition of the aquifers geometry in the studied area thanks to the data acquired by the analysis of geologic sections of drilling and piezometers crossed shells partially or in full. Overall analyses of the piezometric Chronicles of different piezometers located at the level of the dam indicate that the influence of the dam is felt especially in the aquifer carbonate which confirms that the dynamics of this aquifer are highly correlated to the dam’s dynamic. Groundwater maps, high and low-water dam, show a flow that moves towards the threshold of El Haouareb to the discharge of the waters of Ain El Beidha discharge towards the plain of Kairouan. Software FEFLOW 5.2 steady hydrodynamic modeling to simulate the hydraulic threshold at the level of the dam El Haouareb in a satisfactory manner. However, the sensitivity study to the different parameters shows equivalence problems and a fix to calibrate the limestones’ permeability. This work could be improved by refining the timing steady and amending the representation of limestones in the model.

Keywords: Hydrodynamic modeling, lithological modeling, hydraulic, semi-arid, merguellil, central Tunisia

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Authors: Kashif Ahmed

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Recent years researchers have been motivated towards extensive exploring of living organism, which could be utilized effectively in intense industrial conditions. The present study shows enhanced production, purification and characterization of industrial enzyme, invertase (Beta-D-fructofuranosidase) from Penicillium lilacinum. Various agricultural based by-products (cotton stalk, sunflower waste, rice husk, molasses and date syrup) were used as energy source. The highest amount of enzyme (13.05 Units/mL) was produced when the strain was cultured on growth medium containing date syrup as energy source. Yeast extract was used as nitrogen source after 96 h of incubation at incubation temperature of 40º C. Initial pH of medium was 8.0, inoculum size 6x10⁶ conidia and 200 rev/min agitation rate. The enzyme was also purified (7 folds than crude) and characterized. Molecular mass of purified enzyme (65 kDa) was determined by 10 % SDS-PAGE. Lineweaver-Burk Plot was used to determine Kinetic constants (Vmax 178.6 U/mL/min and Km 2.76 mM). Temperature and pH optima were 55º C and 5.5 respectively. MnCl₂ (52.9 %), MgSO₄ (48.9 %), BaCl₂ (24.6 %), MgCl₂ (9.6 %), CoCl₂ (5.7 %) and NaCl (4.2 %) enhanced the relative activity of enzyme and HgCl₂ (-92.8 %), CuSO₄ (-80.2 %) and CuCl₂ (-76.6 %) were proved inhibitors. The strain was showing enzyme activity even at extreme conditions of temperature (up to 60º C) and pH (up to 9), so it can be used in industries.

Keywords: invertase, Penicillium lilacinum, submerged fermentation, industrial enzyme

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Authors: Muhammad Saleem Akhtar, Mushtaq Hussain Lashari, Ejaz Ahmad, Tanveer Ahmad, Laeeq Akbar Lodhi, Ijaz Ahmad, Masood Akhtar

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The objective of this study was to determine the effect of bull exposure continuously or intermittently or its excretory products after calving on postpartum interval to estrus, in Nili-Ravi buffalo. Forty-eight buffaloes of Nili-Ravi breed were allocated one of the four treatments in a totally randomized plan using a 4 x 1 factorial design. The four treatment groups were BEC (Bull Exposed Continuously), BEI (Bull Exposed Intermittently), EPB (Excretory Products of Bull) and BNE (Bull Not Exposed). BEC; buffaloes (n = 12) were exposed continuously to the physical presence of a bull whereas in BEI; buffaloes (n = 12) were exposed intermittently to the physical presence of bull. EPB; buffaloes (n = 12) were exposed to discharge waste (urine and feces) of bull and BNE buffaloes (n = 12) were not exposed to a bull or discharge waste of bulls. Buffaloes were exposed on day 15 after parturition. Day 15 postpartum represented d 0 for each treatment. The postpartum interval from calving to first behavioural estrus was 66.88 days in BEC, 75.12 days in BEI, 77.28 days in EPB and 76.5 days in BNE treatments. Postpartum interval to first behavioural estrus was shorter in BEC than BEI, EPB, and BNE treatments. There was no significant difference in postpartum interval to estrus between BEI, EPB and BNE treatments. In present study, the percentage of buffaloes showing estrus during experimental period was 75.0%, 66.66%, 66.66% and 58.33% in BEC, BEI, EPB and BNE treatments, respectively. The mean serum progesterone concentration did not differ significantly between BEC and other (BEI, EPB, and BNE) treatments. It was concluded that presence of bull has positive effect in reducing calving interval in Nili Ravi buffalo.

Keywords: calving interval, biostimulation, buffalo, bull exposure

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Authors: Sophie Mills, Constantinos Aristotelous, Leila L. Touil, Richard C. W. James

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Objectives: Historical studies of the anatomy of the spinal accessory nerve (SAN) have reported conflicting results regarding its relationship with the internal jugular vein (IJV). A literature review was undertaken to establish the prevalence of anatomical variations of the SAN encountered during routine neck dissection surgery in order to increase awareness and reduce morbidity associated with iatrogenic SAN injury. Materials and Methods: The largest systematic review to date was performed using PRISMA-ScR guidelines, which yielded nine articles following the application of inclusion and exclusion criteria. A case report is also included, which demonstrates the rare anatomical relationship of the SAN traversing a fenestrated IJV, seen for the first time in the senior author’s career. Results: The mean number of dissections per study was 119, of which 55.6% (n=5) studies were performed on cadaver subjects, and 44.4% (n=4) were surgical dissections. Incidences of the SAN lateral to the IJV and medial to the IJV ranged from 38.9%-95.7% and 2.8%-57.4%, respectively. Over half of the studies reported incidences of the SAN traversing the IJV in 0.9%-2.8% of dissections. One study reported an isolated variant of the SAN dividing around the IJV with a prevalence of 0.5%. Conclusion: At the level of the posterior belly of the digastric muscle, the surgeon can anticipate the identification of the SAN lateral to the IJV in approximately three-quarters of cases, whilst around one-quarter are estimated to be medial. A mean of 1.6% of SANs traverses a fenestration of the vein. It is essential for surgeons to be aware of these anatomical variations and their prevalence to prevent injury to vital structures during surgery.

Keywords: anatomical variant, internal jugular vein, neck dissection, spinal accessory nerve

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Authors: Yi-Chuan Cheng, Li-Chi Huang, Yu-Shan Chang

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Introduction: The main purpose of this study was to explore the relationship between the learning number, care knowledge, care skills and maternal confidence in preterm infant care in Taiwan. Background: Preterm infants care has been stressful for mother caring at home. Many programs have been applied for improving the infant care maternal confident. But less to know the learning behavior in mothers of preterm infant. Methods: The sample consisted of 55 mothers with preterm infants were recruited in a neonatal intermediate unit at a medical center in central Taiwan. The self-reported questionnaires including knowledge and skills of preterm infant care scales and maternal confidence scale were used to evaluation, which were conducted during hospitalization, before hospital discharge, and one month after discharge. We performed by using Pearson correlation of the collected data using SPSS 18. Results: The study showed that the learning number and knowledge in preterm infant care was a significant positive correlation (r = .40), and the skills and confidence preterm infant care was positively correlated (r = .89). Conclusions: Study results showed the mother had more learning number in preterm infant care will be stronger knowledge, and the skills and confidence in preterm infant care were also positively correlated. Thus, we found the learning behavior change significant care knowledge. And the maternal confidence change significant with skill on preterm infant’s care. But bondage still needs further study and develop the participation in hospital-based instructional programs, which could lead to greater long-term retention of learning.

Keywords: learning behavior, care knowledge, care skills, maternal confidence

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Authors: Aruma Baduge Kithma De Silva

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Haskap (Lonicera caerulea L.), also known as blue honeysuckle, is a newly commercialized berry crop in Canada. Haskap berries are rich in polyphenols, including, anthocyanins, which are known for potential health-promoting properties. Cyanidin-3-O-glucoside (C3G) is the most abundant anthocyanin of haskap berries. The compound C3G has the ability to reduce the risk of type 2 diabetes (T2D), which has become an increasingly common health issue around the world. The T2D is characterized as a metabolic disorder of hyperglycemia and insulin resistance. It has been demonstrated that C3G has anti-diabetic effects through several ways, including inhibition of dipeptidyl peptidase-4 (DPP-4), reduction of gluconeogenesis, improvement in insulin sensitivity, and inhibition of activities of carbohydrate hydrolyzing enzymes, including α-amylase and α-glucosidase. The goal of this study was to investigate the influence of variety and harvests maturity of haskap on C3G, other fruit quality characteristics and anti-diabetic activities of haskap berries using in vitro studies. The polyphenols present in four commercially grown haskap cultivars, Aurora, Rebecca, Larissa, and Evie harvested at five harvesting dates (H1-H5) apart from 2-3 days, were extracted separately. High-performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) analyzes of polyphenols revealed that haskap berries contain predominantly anthocyanins, flavonols, flavan-3-ols, and phenolic acids. The compound C3G was the most prominent anthocyanin, which is available in approximately 79% of total anthocyanin in four cultivars. The Larissa at H5 contained the highest C3G content. The antioxidant capacity of Evie at H5 was greater than other cultivars. Furthermore, Larissa H5 showed the greatest inhibition of carbohydrate hydrolyzing enzymes including alpha-glucosidase and alpha-amylase. In conclusion, the haskap variety and harvesting date influenced the polyphenol composition and biological properties. The variety Larissa, at H5 harvesting date, contained the highest polyphenol content and the ability of inhibition of the carbohydrate hydrolyzing enzyme as well as DPP4 enzyme in order to reduce type 2 diabetes.

Keywords: anthocyanin, Haskap, type 2 diabetes, polyphenol

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Authors: Adilah Abdul Ghapor, Yong Zulina Zubairi, A. H. M. R. Imon

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Missing value problem is common in statistics and has been of interest for years. This article considers two modern techniques in handling missing data for linear functional relationship model (LFRM) namely the Expectation-Maximization (EM) algorithm and Expectation-Maximization with Bootstrapping (EMB) algorithm using three performance indicators; namely the mean absolute error (MAE), root mean square error (RMSE) and estimated biased (EB). In this study, we applied the methods of imputing missing values in two types of LFRM namely the full model of LFRM and in LFRM when the slope is estimated using a nonparametric method. Results of the simulation study suggest that EMB algorithm performs much better than EM algorithm in both models. We also illustrate the applicability of the approach in a real data set.

Keywords: expectation-maximization, expectation-maximization with bootstrapping, linear functional relationship model, performance indicators

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Authors: Rashid Mahmood, Muhammad Sufyan, Nasir Ahmed

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The MANETs have lessened transportation and decentralized network. There are numerous basis of routing protocols. We derived the MANETs protocol into three major categories like Reactive, Proactive and hybrid. In these protocols, we discussed only some protocols like Distance Sequenced Distance Vector (DSDV), Ad hoc on Demand Distance Vector (AODV) and Dynamic Source Routing (DSR). The AODV and DSR are both reactive type of protocols. On the other hand, DSDV is proactive type protocol here. We compare these routing protocols for network security estimated by network simulator (NS-2). In this dissertation some parameters discussed such as simulation time, packet size, number of node, packet delivery fraction, push time and speed etc. We will construct all these parameters on routing protocols under suitable conditions for network security measures.

Keywords: DSDV, AODV, DSR NS-2, PDF, push time

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Authors: Belahmadi M. S. O., Abdessemed A., Benchiheub M., Doukali H., Kaid Kasbah K. M.

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The aim of this study is to evaluate the quality of leachate generated by the Batna landfill site, and to verify the performance of various advanced oxidation processes, in particular the Fenton and Photo-Fenton systems combined with biological treatment to eliminate the recalcitrant organic matter contained in this effluent, and to preserve reverse osmosis membranes used for leachate treatment. The average values obtained are compared with national and international discharge standards. The results of physico-chemical analyses show that the leachate has an alkaline pH =8.26 and a high organic load with a low oxygen content. Mineral pollution is represented by high conductivity (38.3 mS/cm), high Kjeldahl nitrogen content (1266.504 mg/L) and ammoniacal nitrogen (1098.384 mg/L). The average pollution indicator parameters measured were: BOD5 = 1483.333 mg O2 /L, COD = 99790.244 mg O 2/L, TOC = 22400 mg C/L. These parameters exceed Algerian standards. Hence, there is a necessity to treat this effluent before discharging it into the environment. A comparative study was carried out to estimate the efficiency of two oxidation processes. Under optimum reaction conditions, TOC removal efficiencies of 63.43% and 73.4% were achieved for the Fenton and Photo-Fenton processes, respectively. COD removal rates estimated at 88% and 99.5% for the Fenton and Photo- Fenton processes, respectively. In addition, the Photo-Fenton + bacteria + micro- algae hybrid treatment gave removal efficiencies of around 92.24% for TOC and 99.9% for COD; -0.5 for AOS and 0.01 for CN. The results obtained during this study showed that a hybrid approach combining the PhotoFenton process and biological treatment appears to be a highly effective alternative for achieving satisfactory treatment, which aimed at exploiting the advantages of this method in terms of organic pollutant removal.

Keywords: leachate, landfill, advanced oxidation processes, Fenton and Photo-Fenton systems, biological treatment, organic pollutants

Procedia PDF Downloads 54

Authors: M. A. Badr, A. N. Mohib, M. M. Ibrahim

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The objective of this research is to study the technical and economic performance of wind/diesel/battery (W/D/B) system supplying a remote small gathering of six families using HOMER software package. The electrical energy is to cater for the basic needs for which the daily load pattern is estimated. Net Present Cost (NPC) and Cost of Energy (COE) are used as economic criteria, while the measure of performance is % of power shortage. Technical and economic parameters are defined to estimate the feasibility of the system under study. Optimum system configurations are estimated for two sites. Using HOMER software, the simulation results showed that W/D/B systems are economical for the assumed community sites as the price of generated electricity is about 0.308 $/kWh, without taking external benefits into considerations. W/D/B systems are more economical than W/B or diesel alone systems, as the COE is 0.86 $/kWh for W/B and 0.357 $/kWh for diesel alone.

Keywords: optimum energy systems, remote electrification, renewable energy, wind turbine systems

Procedia PDF Downloads 388

Authors: Anuar Mohd Salleh, Mohd Effendi Daud

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This study presents a kinematic positioning approach which is use the GPS buoy for precise ocean surface monitoring. A GPS buoy data from two experiments have been processed using a precise, medium-range differential kinematic technique. In each case the data were collected for more than 24 hours at nearby coastal site at a high rate (1 Hz), along with measurements from neighboring tidal stations, to verify the estimated sea surface heights. Kinematic coordinates of GPS buoy were estimated using the epoch-wise pre-elimination and the backward substitution algorithm. Test results show the centimeter level accuracy in sea surface height determination can be successfully achieved using proposed technique. The centimeter level agreement between two methods also suggests the possibility of using this inexpensive and more flexible GPS buoy equipment to enhance (or even replace) the current use of tidal gauge stations.

Keywords: global positioning system, kinematic GPS, sea surface height, GPS buoy, tide gauge

Procedia PDF Downloads 529

Authors: M. Mulumpwa, W. W. L. Jere, M. Lazaro, A. H. N. Mtethiwa

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The study considered Seasonal Autoregressive Integrated Moving Average (SARIMA) processes to select an appropriate stochastic model to forecast the monthly data from the Lake Malawi water levels for the period 1986 through 2015. The appropriate model was chosen based on SARIMA (p, d, q) (P, D, Q)S. The Autocorrelation function (ACF), Partial autocorrelation (PACF), Akaike Information Criteria (AIC), Bayesian Information Criterion (BIC), Box–Ljung statistics, correlogram and distribution of residual errors were estimated. The SARIMA (1, 1, 0) (1, 1, 1)12 was selected to forecast the monthly data of the Lake Malawi water levels from August, 2015 to December, 2021. The plotted time series showed that the Lake Malawi water levels are decreasing since 2010 to date but not as much as was the case in 1995 through 1997. The future forecast of the Lake Malawi water levels until 2021 showed a mean of 474.47 m ranging from 473.93 to 475.02 meters with a confidence interval of 80% and 90% against registered mean of 473.398 m in 1997 and 475.475 m in 1989 which was the lowest and highest water levels in the lake respectively since 1986. The forecast also showed that the water levels of Lake Malawi will drop by 0.57 meters as compared to the mean water levels recorded in the previous years. These results suggest that the Lake Malawi water level may not likely go lower than that recorded in 1997. Therefore, utilisation and management of water-related activities and programs among others on the lake should provide room for such scenarios. The findings suggest a need to manage the Lake Malawi jointly and prudently with other stakeholders starting from the catchment area. This will reduce impacts of anthropogenic activities on the lake’s water quality, water level, aquatic and adjacent terrestrial ecosystems thereby ensuring its resilience to climate change impacts.

Keywords: forecasting, Lake Malawi, water levels, water level fluctuation, climate change, anthropogenic activities

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Authors: Kaige Shi, Chao Jiang, Xin Li

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The swirl gripper is an electrically activated noncontact handling device that uses swirling airflow to generate a lifting force. This force can be used to pick up a workpiece placed underneath the swirl gripper without any contact. It is applicable, for example, in the semiconductor wafer production line, where contact must be avoided during the handling and moving of a workpiece to minimize damage. When a workpiece levitates underneath a swirl gripper, the gap height between them is crucial for safe handling. Therefore, in this paper, we propose a method to estimate the levitation gap height by detecting pressure at two points. The method is based on theoretical model of the swirl gripper, and has been experimentally verified. Furthermore, the force between the gripper and the workpiece can also be estimated using the detected pressure. As a result, the nonlinear relationship between the force and gap height can be linearized by adjusting the rotating speed of the fan in the swirl gripper according to the estimated force and gap height. The linearized relationship is expected to enhance handling stability of the workpiece.

Keywords: swirl gripper, noncontact handling, levitation, gap height estimation

Procedia PDF Downloads 119